Separable attachment-plug.



H. HUBBELL. SEPARABLE ATTACHMENT PLUG.

APPLIGATION FILED JAN. 2, 1912. l @6%,833@

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O 6 c m m m J V 5 5 2 2 2 4 4 I 2x A 2 2 a E 6 4 7 2 m m n W ATTORNEY SHEAR-ABLE ATTACHMENT-PLUG.

Specification of Letters Patent.

iatented June 1'7 1913.

Application filed January'2, 1912. Serial No. 669,253.

To all whom it may concern Be it known that I, HARVEY HUBBELL, a citizen of the United States, residing .at Bridgeport, county of Fairfield, State of Connecticut, have invented an Improvement in Separable Attachment-Plugs, of which the following is a specification.

This invention has for its objects to simplify and to generally improve the construction and operation of separable attachment lugs.

Vith these and other objects in view the invention consists in certain novel constructions and-combinations of parts which I will now describe, and then specifically point out in the"clainis hereunto appended. V

In the accompanying drawing forming a part of this specification, Figure 1 is a longitudinal section on an enlarged scale, of the base of my novel attachment plug detached; Fig. 2 an elevation of one of the spring contacts detached, the .one toward the right as seen in Fig. 1; Fig. .3 a section ,of the cap detached on the line 33 in Fig. 5, looking in the direction of the arrows, the binding screw being partly turned out; Fig. 4 a section of the cap .on the line 4-4 in Fig. 5, looking in the direction of the arrows; Fig. 5 a plan view of the cap detached; Fig. 6 a section of a variant form of cap which is provided with a cord grip, the section line being indicatedby (S-s6 in Fig. 7 and Fig. 7 is a plan view corresponding with Fig. 6.

10 denotes the base and 11 the cap, both of which are made of insulating material, and 12 denotes the screw shell. The base, has an external thread molded thereonz which'is engaged by the screw shell in the usual manner.

13 and 14 denote the base contacts which lie in recesses in the base, and 15 the con tact blades which project from the-cap. The contact blades are shown as rounded at their ends for convenience in engagement with the base contacts and asprovided on 0pposite sides with recesses 16. The base contacts each comprise spring plates, indicated by 17 one or both being provided with inwardly extending lugs or indentations 18 at their edges (preferably formed by striking in the metalat the edges of the plates.)

cutw ard slightly,

adapted to drop into and engage the recesses in the contact blades when the base and cap are connected, thus insuring an effective electrical connection between the contact blades and the base contacts and also an effective locking together of the two members. In making a connection, the rounded ends of the contact blades pass between the spring plates, the ends thereof engaging the lugs 18 and springing the plates outward until the recesses 16 are in coincidence with the lugs when the lugs will drop into the recesses and will retain the contact blades and spring plates in engagement.

Thespring plates of base contact 13 are secured to a bracket 19 which is held in place by a center screw 20 and serves as .a center contact for a socket (not .shown). The spring plates of base contact 14 are secured to a bracket 21 which rests upon a ledge on the base-and is engaged and held in place by the overlying flange 22 of the screw shell. The parts in the base are thus reduced to the lowest possible number and the assembling is made perfectly simple. The contact blades are provided with base plates 23 which are engaged by the binding screws 24. A novel feature {of the present cap is that .the contact blades are secured in place in the process of manufacture by the molding of the base plates into the material of the cap, the binding screws being left exposed in recesses 25.

.31 denotes wires, .32 cords and 33 a cable. In .the form of cap illustrated in Figs. 3, e and 5, the end of the cable is received in a central recess 26 and the cords inclosing the wires are passed through holes 27 which intersect with or lead into binding screw recesses 25. The ends of the cords are stripped off leaving the wires exposed. The binding screw recesses just receive the binding screws freely and are ordinarily beveled as shown, for" convenience in wiring. The wires are drawn through holes 27, ,passed around the binding screws in the usual manner and the screws are .then tightened up. The adthrough the cap but-are always retained .well

down in the recesses by the binding screws,

I binding screws through holes 27 the same as before. At the base of recess 26 I provide a cone 28. The recess is threaded and is engaged by a screw plug 29 having a central hole 30 to receive the cable. .The cords from the cable pass on opposite sides of the cone through the holes 27 and are gripped between the cone. and theend of the screw plug, the

inner end of hole 30 being preferably cham- -fered off, as shown, to provide a gripping surface parallel with the cone. In assembling this form, the cable is passed into hole 30, the cords are passed through holes 27 and the wiresengaged with the binding screws, then the cords are slackened slightly and the screw plug is turned down to place, clamping the cords, as already described, so that any pull upon the cable is taken up by the grip of the-screw plug and cone upon the cords and-n0 strain whatever can be placed upon the connection of the wires to the binding screws. v

Having 'thus described my invention I claim: v.

1. A separable attachment plug comprising a base, a cap, fiat contact blades carried by said cap and having theiropposite edges.

cut away to'form recesses, and flat contact blades carried by said base the opposite ,edges of the last mentioned blades being provided with lugs or indentations adapted to enter the recesses of the first mentioned blades when the cap and base are united.

2. A separable attachment plug-comprising a base, a cap, fiat contact blades'carried by said cap and having their opposite edges cut away to form recesses, and flat contact blades carried by said base and arranged in pairs, the opposite edges of one of the plates of each pair being provided with lugs or indentations adapted to enter the recesses of the 'first mentioned blades when the cap and base ,arenunitedi 3. An attachment plu'g'cap formed of insu'lating material and provided with spaced apart recesses, contact blades provided with base plates embedded within said insulating material and each having a portion projecting into one of said recesses, and binding screws located in said recesses and engaging tlie projecting portion of the respective base p ates. v

4. An attachment plug cap formed of insulating material provided with a central bore and spaced apart recesses, said cap being'provided with holes. extending from said bore to said recesses, contact blades provided with baseiplates embedded within said insulating material and each having a portion PI'OJGCtlng into one of sa d recesses, and

binding screws located in said recesses and engaging the projecting portions of the respective base plates.

5. An attachment plug base provided with recesses, brackets carrying contact-s which extend into said recesses, a center screw ensaid baseand provided with a flange engaging said shoulder to hold the second bracket in place, and a center screw for securing the other bracket in place.

7. An attachment plug base provided with an annular ledge and longitudinal recesses,

brackets carrying contacts which; extend into said recesses, said brackets being pro-I vided with angular supporting portions, thexsupporting portion of one bracket resting uponsaid ledge, a screw shell having a threaded engagement with said' base and provided with a flange overlying said ledge and engaging the supporting'portion of the 'lastmentioned bracket, and a center screw.

supporting bracket;

8. In a separable attachment plug, the combination with a base having a'ledge and engaging the angular portion of the other longitudinal. recesses, contacts'lying wholly within said recesses and insulated by the material of'the base and brackets by which i said contacts are carried, one of, said brackets serving as -a center contact, of a screw engaging said bracket to hold the contact in place and a screw shell'having an overlying flange between which and-the ledge the other bracket is gripped.

9. An attachment plug base provided with an annular ledge and longitudinal recesses, brackets carrying contacts which extend into said recesses, one of said brackets having a shoulder resting upon said ledge, a screw shell surrounding said base and having a threaded engagement therewith, said screw shell being provided with a flange engaging said shoulder to hold the second bracket in place, and a center screw for Se, curing the other bracket in place.

10. An attachment plug base provided with an annular ledge and longitudinal reces'ses, brackets carrying contacts which exlend into said recesses, said brackets being center screw engaging (he angular portion provided with angular supporting portions, of the other supporting bracket. 10 'the supporting portion of one bracket restln testimony whereof I afiix my signaling upon said ledge, a screw shell surroundlure in presence of two witnesses.

ing said base and having nv threaded engnge- HARVEY H U BBELL.

nient therewith, said screw shell being pro- Witnesses; vlded with a flange engaging said shoulder A. M Woosmm to hold the second bracket in place, and a l S. ATHERTON 

